#ifndef _LINUX_IPC_H
#define _LINUX_IPC_H

#include <linux/types.h>

#define IPC_PRIVATE ((__kernel_key_t) 0)  

struct ipc_perm
{
	__kernel_key_t	key;
	__kernel_uid_t	uid;
	__kernel_gid_t	gid;
	__kernel_uid_t	cuid;
	__kernel_gid_t	cgid;
	__kernel_mode_t	mode; 
	unsigned short	seq;
};

/* resource get request flags */
#define IPC_CREAT  00001000   /* create if key is nonexistent */
#define IPC_EXCL   00002000   /* fail if key exists */
#define IPC_NOWAIT 00004000   /* return error on wait */

/* these fields are used by the DIPC package so the kernel as standard
   should avoid using them if possible */
   
#define IPC_DIPC 00010000  /* make it distributed */
#define IPC_OWN  00020000  /* this machine is the DIPC owner */

/* 
 * Control commands used with semctl, msgctl and shmctl 
 * see also specific commands in sem.h, msg.h and shm.h
 */
#define IPC_RMID 0     /* remove resource */
#define IPC_SET  1     /* set ipc_perm options */
#define IPC_STAT 2     /* get ipc_perm options */
#define IPC_INFO 3     /* see ipcs */

#ifdef __KERNEL__

/* special shmsegs[id], msgque[id] or semary[id]  values */
#define IPC_UNUSED	((void *) -1)
#define IPC_NOID	((void *) -2)		/* being allocated/destroyed */

#endif /* __KERNEL__ */

#endif /* _LINUX_IPC_H */
